Random samples of residents aged 18-74 years who lived in four central California cities (baseline, n=1,056 men and 1,183 women) were evaluated in 1979-1980 and approximately every 2 years thereafter to obtain four independent samples.

Moreover, every subject in the initial independent samples was asked to retum for follow-up every 2 years thereafter ; subjects who completed all four examinations constituted the cohort sample (n=408 men and 499 women).

Two medium-sized cities recelved health education and two similarly sized cities served as controls.

Results indicated little consistent evidence of a treatment effect on physical activity knowledge, attitudes, or self-efficacy in either men or women.

Among physical activity measures, there was an indication of a positive treatment effect for men in the independent samples for estimated daily energy expenditure and percent participation in vigorous activities (p<0.01), and for women in the independent (p=0.014) and cohort (p<0.01) samples for engagement in the number of moderate activities. (...)